A U.N. official in Ivory Coast says forces loyal to incumbent president Laurent Gbagbo are "indiscriminately" shelling areas seen as backing Gbagbo's rival, Alassane Ouattara.

Human rights official Guillaume Ngefa told a news conference Thursday that the shelling and other attacks have killed at least 50 people in the last week, including five children, and wounded dozens more.

Ngefa, who was speaking in Abidjan, said the attacks bring the confirmed death toll from post-election violence in Ivory Coast up to 462.

Gbagbo government has denied using heavy weapons against civilians, and accuses the U.N. of siding with Mr. Ouattara in the Ivory Coast political crisis.

Gbagbo has rejected calls from the U.N., African Union, and the west African bloc ECOWAS to give up power. All three bodies recognize Ouattara as the winner of last November's presidential election.

Fighting between Ouattara and Gbagbo supporters has intensified in recent weeks, sparking fears that Ivory Coast will fall back into civil war.

A brief war in 2002 left Ivory Coast split into a rebel-controlled north and a government controlled south. The former rebels are now backing Ouattara, and have captured several towns in the country's west.